What are the required steps to convert base 10 integer
number 111 111 001 551 to signed binary code (in base 2)?
- A signed integer, written in base ten, or a decimal system number, is a number written using the digits 0 through 9 and the sign, which can be positive (+) or negative (-). If positive, the sign is usually not written. A number written in base two, or binary, is a number written using only the digits 0 and 1.
1. Divide the number repeatedly by 2:
Keep track of each remainder.
Stop when you get a quotient that is equal to zero.
- division = quotient + remainder;
- 111 111 001 551 ÷ 2 = 55 555 500 775 + 1;
- 55 555 500 775 ÷ 2 = 27 777 750 387 + 1;
- 27 777 750 387 ÷ 2 = 13 888 875 193 + 1;
- 13 888 875 193 ÷ 2 = 6 944 437 596 + 1;
- 6 944 437 596 ÷ 2 = 3 472 218 798 + 0;
- 3 472 218 798 ÷ 2 = 1 736 109 399 + 0;
- 1 736 109 399 ÷ 2 = 868 054 699 + 1;
- 868 054 699 ÷ 2 = 434 027 349 + 1;
- 434 027 349 ÷ 2 = 217 013 674 + 1;
- 217 013 674 ÷ 2 = 108 506 837 + 0;
- 108 506 837 ÷ 2 = 54 253 418 + 1;
- 54 253 418 ÷ 2 = 27 126 709 + 0;
- 27 126 709 ÷ 2 = 13 563 354 + 1;
- 13 563 354 ÷ 2 = 6 781 677 + 0;
- 6 781 677 ÷ 2 = 3 390 838 + 1;
- 3 390 838 ÷ 2 = 1 695 419 + 0;
- 1 695 419 ÷ 2 = 847 709 + 1;
- 847 709 ÷ 2 = 423 854 + 1;
- 423 854 ÷ 2 = 211 927 + 0;
- 211 927 ÷ 2 = 105 963 + 1;
- 105 963 ÷ 2 = 52 981 + 1;
- 52 981 ÷ 2 = 26 490 + 1;
- 26 490 ÷ 2 = 13 245 + 0;
- 13 245 ÷ 2 = 6 622 + 1;
- 6 622 ÷ 2 = 3 311 + 0;
- 3 311 ÷ 2 = 1 655 + 1;
- 1 655 ÷ 2 = 827 + 1;
- 827 ÷ 2 = 413 + 1;
- 413 ÷ 2 = 206 + 1;
- 206 ÷ 2 = 103 + 0;
- 103 ÷ 2 = 51 + 1;
- 51 ÷ 2 = 25 + 1;
- 25 ÷ 2 = 12 + 1;
- 12 ÷ 2 = 6 + 0;
- 6 ÷ 2 = 3 + 0;
- 3 ÷ 2 = 1 + 1;
- 1 ÷ 2 = 0 + 1;
2. Construct the base 2 representation of the positive number:
Take all the remainders starting from the bottom of the list constructed above.
111 111 001 551(10) = 1 1001 1101 1110 1011 1011 0101 0101 1100 1111(2)
3. Determine the signed binary number bit length:
The base 2 number's actual length, in bits: 37.
- A signed binary's bit length must be equal to a power of 2, as of:
- 21 = 2; 22 = 4; 23 = 8; 24 = 16; 25 = 32; 26 = 64; ...
- The first bit (the leftmost) is reserved for the sign:
- 0 = positive integer number, 1 = negative integer number
The least number that is:
1) a power of 2
2) and is larger than the actual length, 37,
3) so that the first bit (leftmost) could be zero
(we deal with a positive number at this moment)
=== is: 64.
4. Get the positive binary computer representation on 64 bits (8 Bytes):
If needed, add extra 0s in front (to the left) of the base 2 number, up to the required length, 64:
111 111 001 551(10) Base 10 integer number converted and written as a signed binary code (in base 2):
111 111 001 551(10) = 0000 0000 0000 0000 0000 0000 0001 1001 1101 1110 1011 1011 0101 0101 1100 1111
Spaces were used to group digits: for binary, by 4, for decimal, by 3.